This invention relates to a simplified method of recycling vehicle trim components and other scrap materials incorporating urethane foam.
In the prior art, many components which are utilized in automobiles include a significant portion of urethane foam. As one example, the seat foam typically utilized to provide cushion in a vehicle seat is a urethane-based foam. Another example is found in vehicle headliners. The seat foam is typically trimmed prior to insertion into the seat, and thus, at the manufacturing site, there is a good deal of excess or waste foam trimmed away from the final desired foam. The same is true of headliners, which are initially molded and then cut to a desired shape.
Thus, at a vehicle trim manufacturing site, there is often a good deal of waste material. A large volume of waste material includes polyurethane foam. In some cases, the waste material could include many other materials. As an example, a vehicle headliner could include nylon, polyester, cellulose films, glass fibers, and even natural fiber layers. In the past, it has been very difficult to recycle these components since they include so many distinct materials.
One recent method mixed these materials into a shredded fluff, and then mixed a binder into the fluff. This invention is disclosed in U.S. Pat. No. 5,807,513. In this patent, it was recognized that in order to provide binder to all of the several pieces of fluff, the binder would be desirably carried in a water.
Further, it is known in the prior art to take flexible polyurethane foam, only the foam, and grind it into a powder, with particles on the order of the microns. This powder has then been pressed into a sheet of material. While this has been proposed as a way to utilize waste polyurethane foam, it has not been used in production. Moreover, it has never been proposed to use ground polyurethane foam as a binder for other non-polyurethane materials.
Many types of materials are generated as waste in a vehicle trim manufacturing plant. While polyurethane foam-containing materials may benefit from the above prior art, there are also many other materials which have not been as adaptable to recycling.
Further, while industry does desirably wish to gain recycling as a benefit, in the end, cost is an overriding factor. Thus, if the recycling is not cost effective, it will not occur in large part. The above-described method of grinding into a powder is not cost effective.
The present invention is directed to a method of using polyurethane foam as a binder.